/*-
 * Copyright (c) 2004-2005 David Schultz <das@FreeBSD.ORG>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifdef __arm__
#include <arm/fenv.h>
#else /* __arm__ */

#ifndef	_FENV_H_
#define	_FENV_H_

#include <sys/cdefs.h>
#include <sys/_types.h>

#ifndef	__fenv_static
#define	__fenv_static	static
#endif

/* The high 32 bits contain fpcr, low 32 contain fpsr. */
typedef	__uint64_t	fenv_t;
typedef	__uint64_t	fexcept_t;

/* Exception flags */
#define	FE_INVALID	0x00000001
#define	FE_DIVBYZERO	0x00000002
#define	FE_OVERFLOW	0x00000004
#define	FE_UNDERFLOW	0x00000008
#define	FE_INEXACT	0x00000010
#define	FE_ALL_EXCEPT	(FE_DIVBYZERO | FE_INEXACT | \
			 FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW)

/*
 * Rounding modes
 *
 * We can't just use the hardware bit values here, because that would
 * make FE_UPWARD and FE_DOWNWARD negative, which is not allowed.
 */
#define	FE_TONEAREST	0x0
#define	FE_UPWARD	0x1
#define	FE_DOWNWARD	0x2
#define	FE_TOWARDZERO	0x3
#define	_ROUND_MASK	(FE_TONEAREST | FE_DOWNWARD | \
			 FE_UPWARD | FE_TOWARDZERO)
#define	_ROUND_SHIFT	22

__BEGIN_DECLS

/* Default floating-point environment */
extern const fenv_t	__fe_dfl_env;
#define	FE_DFL_ENV	(&__fe_dfl_env)

/* We need to be able to map status flag positions to mask flag positions */
#define _FPUSW_SHIFT	8
#define	_ENABLE_MASK	(FE_ALL_EXCEPT << _FPUSW_SHIFT)

#define	__mrs_fpcr(__r)	__asm __volatile("mrs %0, fpcr" : "=r" (__r))
#define	__msr_fpcr(__r)	__asm __volatile("msr fpcr, %0" : : "r" (__r))

#define	__mrs_fpsr(__r)	__asm __volatile("mrs %0, fpsr" : "=r" (__r))
#define	__msr_fpsr(__r)	__asm __volatile("msr fpsr, %0" : : "r" (__r))

int feclearexcept(int);
int fegetexceptflag(fexcept_t *, int);
int fesetexceptflag(const fexcept_t *, int);
int feraiseexcept(int);
int fetestexcept(int);
int fegetround(void);
int fesetround(int);
int fegetenv(fenv_t *);
int feholdexcept(fenv_t *);
int fesetenv(const fenv_t *);
int feupdateenv(const fenv_t *);
int feenableexcept(int);
int fedisableexcept(int);
int fegetexcept(void);

#define	feclearexcept(a)	__feclearexcept_int(a)
#define	fegetexceptflag(e, a)	__fegetexceptflag_int(e, a)
#define	fesetexceptflag(e, a)	__fesetexceptflag_int(e, a)
#define	feraiseexcept(a)	__feraiseexcept_int(a)
#define	fetestexcept(a)		__fetestexcept_int(a)
#define	fegetround()		__fegetround_int()
#define	fesetround(a)		__fesetround_int(a)
#define	fegetenv(e)		__fegetenv_int(e)
#define	feholdexcept(e)		__feholdexcept_int(e)
#define	fesetenv(e)		__fesetenv_int(e)
#define	feupdateenv(e)		__feupdateenv_int(e)
#define	feenableexcept(a)	__feenableexcept_int(a)
#define	fedisableexcept(a)	__fedisableexcept_int(a)
#define	fegetexcept()		__fegetexcept_int()

__fenv_static inline int
__feclearexcept_int(int __excepts)
{
	fexcept_t __r;

	__mrs_fpsr(__r);
	__r &= ~__excepts;
	__msr_fpsr(__r);
	return (0);
}

__fenv_static inline int
__fegetexceptflag_int(fexcept_t *__flagp, int __excepts)
{
	fexcept_t __r;

	__mrs_fpsr(__r);
	*__flagp = __r & __excepts;
	return (0);
}

__fenv_static inline int
__fesetexceptflag_int(const fexcept_t *__flagp, int __excepts)
{
	fexcept_t __r;

	__mrs_fpsr(__r);
	__r &= ~__excepts;
	__r |= *__flagp & __excepts;
	__msr_fpsr(__r);
	return (0);
}

__fenv_static inline int
__feraiseexcept_int(int __excepts)
{
	fexcept_t __r;

	__mrs_fpsr(__r);
	__r |= __excepts;
	__msr_fpsr(__r);
	return (0);
}

__fenv_static inline int
__fetestexcept_int(int __excepts)
{
	fexcept_t __r;

	__mrs_fpsr(__r);
	return (__r & __excepts);
}

__fenv_static inline int
__fegetround_int(void)
{
	fenv_t __r;

	__mrs_fpcr(__r);
	return ((__r >> _ROUND_SHIFT) & _ROUND_MASK);
}

__fenv_static inline int
__fesetround_int(int __round)
{
	fenv_t __r;

	if (__round & ~_ROUND_MASK)
		return (-1);
	__mrs_fpcr(__r);
	__r &= ~(_ROUND_MASK << _ROUND_SHIFT);
	__r |= __round << _ROUND_SHIFT;
	__msr_fpcr(__r);
	return (0);
}

__fenv_static inline int
__fegetenv_int(fenv_t *__envp)
{
	__uint64_t fpcr;
	__uint64_t fpsr;

	__mrs_fpcr(fpcr);
	__mrs_fpsr(fpsr);
	*__envp = fpsr | (fpcr << 32);

	return (0);
}

__fenv_static inline int
__feholdexcept_int(fenv_t *__envp)
{
	fenv_t __r;

	__mrs_fpcr(__r);
	*__envp = __r << 32;
	__r &= ~(_ENABLE_MASK);
	__msr_fpcr(__r);

	__mrs_fpsr(__r);
	*__envp |= (__uint32_t)__r;
	__r &= ~(_ENABLE_MASK);
	__msr_fpsr(__r);
	return (0);
}

__fenv_static inline int
__fesetenv_int(const fenv_t *__envp)
{

	__msr_fpcr((*__envp) >> 32);
	__msr_fpsr((fenv_t)(__uint32_t)*__envp);
	return (0);
}

__fenv_static inline int
__feupdateenv_int(const fenv_t *__envp)
{
	fexcept_t __r;

	__mrs_fpsr(__r);
	fesetenv(__envp);
	feraiseexcept(__r & FE_ALL_EXCEPT);
	return (0);
}

#if __BSD_VISIBLE

static inline int
__feenableexcept_int(int __mask)
{
	fenv_t __old_r, __new_r;

	__mrs_fpcr(__old_r);
	__new_r = __old_r | ((__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT);
	__msr_fpcr(__new_r);
	return ((__old_r >> _FPUSW_SHIFT) & FE_ALL_EXCEPT);
}

static inline int
__fedisableexcept_int(int __mask)
{
	fenv_t __old_r, __new_r;

	__mrs_fpcr(__old_r);
	__new_r = __old_r & ~((__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT);
	__msr_fpcr(__new_r);
	return ((__old_r >> _FPUSW_SHIFT) & FE_ALL_EXCEPT);
}

static inline int
__fegetexcept_int(void)
{
	fenv_t __r;

	__mrs_fpcr(__r);
	return ((__r & _ENABLE_MASK) >> _FPUSW_SHIFT);
}

#endif /* __BSD_VISIBLE */

__END_DECLS

#endif	/* !_FENV_H_ */

#endif /* __arm__ */